A former Yale University laboratory worker will plead guilty to killing 24-year-old graduate student Annie Le days before she was to be married, his lawyer said.

Raymond Clark will enter his plea tomorrow before Connecticut Superior Court Judge Roland Fasano in New Haven, Clark’s lawyer, Beth Merkin, said in a phone interview Tuesday. Clark pleaded not guilty to murder and felony-murder charges in January last year.

“We anticipate a change of plea,” Merkin said yesterday. She declined to comment further, including whether Clark will plead to murder or a lesser charge.

Clark, 26, was arrested in September 2009 and is being held on $3 million bail. He’s accused of strangling Le, a pharmacology student, five days before her Sept 13, 2009, wedding. Clark cleaned mouse cages in the Yale lab building where her body was found.

Le’s body was discovered hidden behind a wall in the basement of the Yale School of Medicine research lab at 10 Amistad Street in New Haven the day she was to be married. The Office of Connecticut’s Chief Medical Examiner said Le died of “traumatic asphyxiation due to neck compression.”

Le, a Vietnamese-American who was studying for her doctorate, was from Placerville, California, according to a September 2009 Yale University statement. She graduated from the University of Rochester, in New York, where she met her fiance, Jonathan Widawsky, the university said.

Clark was suspended from his job when he was arrested, Yale University President Richard Levin said in a 2009 statement.